Charles Day is Wave Hill’s Ruth Rea Howell Horticultural Interpreter.
Every fall, one of the most commonly heard questions is: “What is that patch of purple/pink flowers?” The answer is autumn crocus, an extraordinary plant which, after growing a crop of large, strap-like leaves in spring, goes dormant all summer and then suddenly pops up as a mass of flowers in September into October.
Although called “autumn crocus,” it is actually a species of colchicum and not a true crocus. To add to the confusion, there are indeed species of autumn-blooming crocuses which are true crocuses, including Crocus sativus, the saffron crocus.
They bloom at the same time but should never be treated the same. All parts of autumn crocus (colchicum) are poisonous—which is good because deer will not eat them, but very bad if you do!
There are many species of colchicum and several selections (cultivars), some pink, others purple and even pure white. They can be spotted in various places around the grounds, including the fine display along the edge of the Lower Lawn, just beside the main path between the Perkins Visitor Center and Wave Hill House.